It was, said Meghan Markle, in an exclusive BBC television interview, “sweet and natural and very romantic.” Prince Harry, her prince, even got on one knee to propose to the American actress — who has been married before — ending months of speculation about their possible engagement, while inviting more speculation about the upcoming Royal wedding. Before those invites go out, we hoped to address some fundamentals, such as why a grown man had to ask his 91-year-old grandmother for permission to pop the question.

Queen Elizabeth II is the Queen, after all, so…why did her 33-year-old grandson have to get her permission to marry Markle?

Up until 2015, all male-line descendants of King George II — he died in 1760 — had to ask for the British monarch’s permission to marry for the union to be recognized in the British Isles. Meaning Obscure Prince So-and-So, from such and such a place, would have to get the Queen to sign off on the union — just as Prince Ernst August of Hanover did before marrying Princess Caroline of Monaco in 1999. Obtaining the Queen’s signature to wed among the hereditary-titled-set became a neat bit of family-tree kitsch, for some, where for others it was a ridiculous custom that thankfully ceased with the passage of the Succession of the Crown Act. Now only the top six people in line to the throne have to get royal permission to tie the knot. Prince Harry is fifth in line after his father, Charles, brother William, and nephew and niece (George and Charlotte). And so off to Grandma he did go to receive her blessing.

We know Edward VIII abdicated to marry the twice-divorced American, Wallis Simpson in 1937. Less known is that Canada actually had a voice in the conversation, pre-abdication, about how to handle England’s lovesick King.

It is true: Edward had a thing for Canada long before he had a thing for Wallis Simpson, a romance dating back to 1919, when he laid the foundation stone of the Peace Tower in Ottawa, officially opened the Canadian National Exhibition in Toronto and went on a three-day canoe trip on the Nipigon River. Edward later bought a ranch in Alberta, donated the Prince of Wales Trophy to the NHL (presented today to the league’s Eastern Conference champions) and, according to author and royal historian, Carolyn Harris, always thought of himself as “Canadian in the context of his time in Canada.” Canada was a land of possibility. And so when Edward, the besotted, appeared determined to marry Simpson, there was some hope in British circles that Canadian prime minister Mackenzie King might talk some Canadian with him — and convince him to ditch his would-be American bride. No luck. Mackenzie King, wishing to avoid international scandal, quietly disagreed with the union but publicly kept quiet, more or less, expressing confidence that the King, being a King, would surely do what was right. In hindsight, perhaps Edward did: The abdicated king became a fan-boy of Nazi Germany (and Hitler), sympathies that would not have played well at home when German planes were bombing London during the Blitz.

Times change, even in families where the simple act of being born puts you in line for the British throne. The Queen’s younger sister, Princess Margaret, was pressured not to marry Peter Townsend, a dashing war hero, in the 1950s because he was divorced. Townsend was transferred to Belgium. He married someone else. Margaret also married someone else, and later divorced, establishing a pattern of ill-fated matches that three out of four of the Queen’s own children have stuck to (Prince Charles and Diana Spencer; Prince Andrew and Sarah Ferguson; Princess Anne and Mark Phillips). But here’s the good news: The Church of England, of which the Queen is the head, altered its rules in 2002, and now allows divorced individuals to marry in the church. So Harry and Meghan could, should they wish, tie the knot — and tempt their fate — with a ceremony in St. Paul’s Cathedral, where Prince Charles and Diana did the deed on July 29, 1981.

Markle also went to an all-girls Catholic private school in California. Is the Catholic thing going to be a problem?

Marrying a Catholic used to be as sinful as marrying a divorcee for potential monarchs, and maybe even more so, since a would-be monarch’s Catholicism supposedly jeopardized the safety of the Crown itself. Markle, in theory, as the old Anglican slur goes, is a “papist,” and thus loyal, in theory, to the Pontiff in Rome instead of the sovereign, Queen Elizabeth II — head of the Church of England — and her future grandmother-in-law. Barring Catholics from the throne was enshrined in the Act of Settlement of 1701 since, in the language of the day, “it hath been found by experience that it is inconsistent with the safety and welfare of this Protestant kingdom to be governed by a papist prince.” (Said papist was King James II, who was overthrown by William of Orange in 1688). The Succession to the Crown Act of 2013 erased the anti-Catholic marital provision from the Bill of Rights, as well as any language pertaining to “marrying a papist.”

If Prince Harry winds up on the throne would Rachel Meghan Markle become Queen Meghan?

Yes. If calamity strikes, and Harry as we know him now, becomes King Henry IX, Markle will be Queen. The odds of this actually occurring are unlikely, indeed, but surprises do happen in Royal Houses. Through the centuries several unsuspecting second sons (Henry VIII, Charles I, George V and George VI) and daughters (Elizabeth I and Queen Anne) have suddenly found themselves on the throne. In the meantime: God Save the Queen.